Mechanism for controlling the feeding and advancing of blanks



Feb. 22, 1938.

w. w. DAVIDSON MECHANISM FOR CONTROLLING THE FEEDING AND ADVANCING OF BLANKS Filed May 9, 1936 5 Sheets-Sheet l Feb. 22, 1938. w, w, DAWSON 2,108,800

MECHANISM FOR CONTROLLING THE FEEDING AND ADVANCING OF BLANKS Filed May 9, 1956 5 Sheets-Shae 2 Feb. 22, 1930. w, W AW 2,108,800

MECHANISM FOR CONTROLLING THE FEEDING AND ADVANCING OF BLANKS Filed May 9, 1956 5 Sheets-Sheet 5' Feb. 22, 1938. w, w DAVIDSON 2,108,800

MECHANISM FOR CONTROLLING THE FEEDING AND ADVANCING OF BLANKS Filed May 9, 1936 s Sheets-Sheet 4 Feb, 22, 1938. wQw. D VIDSON 2,108,809

MECHANISM FOR CONTROLLING THE FEEDING AND ADVANCING OF BLANKS Filed May 9, 1956 5 Sheets-Sheet 5 Patented Feb. 22, 1938 UNITED STATES PATENT OFFICE MECHANISM FOR CONTROLLING THE FEED- ING AND ADVANCING F BLANKS 17 Claims.

This invention relates to an improved machine or mechanism for controlling the separating and advancing of blanks, particularly sheets of paper, envelopes and the like, from a pack to a position where they can be grasped or picked up by the mechanism of an associated machine, such as a Multigraph" printing machine, or the like.

The advancement of blanks to a definite position so that the impressions made on the several blanks of a series shall be in substantial register, has been the object of many inventions, but so far as I know, no one, until the present invention was developed, was able to produce a simple machine which could be produced at relatively low cost and which would be accurate in registration within practical limits.

In advancing a blank from a pack, there is bound to be more or less slippage between the advancing means and the blank, or the overthrow of a blank due to advancement thereof by friction with the previously fed blank and this is especially noticeable where the blank is advanced by means of a friction device.

Again when the blank reaches its final ad vanced position, where it is to be grasped by the mechanism of the associated machine, if a rigid stop is provided at the pick up position of the associated machine, the blank may be pushed against the stop with suflicient force to crumple it, or it may not quite reach the stop.

I have conceived and developed means for advancing a blank from a pack to a position for engagement by the pick up mechanism of the associated machine, whereby satisfactory registration of impressions, imprinted on successive blanks may be obtained, and which comprises a friction member for advancing the blanks actuated by suitable operating connection with a driven member, to which, in operation, definite movement is imparted.

As used herein, right and left refer to different sides of the machine when viewed from the rear.

In accordance with the invention, when the blank is suiliciently advanced it operates to stop the application of power to the advancing means.

In the preferred construction, the advancement of blanks from the pack may be described as being effected in two stages by a friction memher and a controlling operating lever, completion of the first stage being determined by advancement of a blank into position to operate a control member, which occurs when the leading edge of a blank attains a predetermined, definite position relative to the pick up devices of the associated machine, and when the operating lever is a definite, predetermined, and measured distance from a stop which limits its blank advancing movement. Contact of said lever with said stop defines completion of the second stage of the advancement of a blank; the relation being such that movement of the operating lever from its position at the completion of the first stage of advancement of a blank into contact with said stop, will be accurately just sufficient, within practical limits, to advance the blank into predetermined position for engagement by the pick up mechanism of said associated machine, for the accurate registration desired.

To the end of accomplishing the above and other desirable and advantageous results, the invention consists in the means herein fully disclosed and particularly pointed out in the appended claims, the accompanying drawings, forming part of this specification, and the following description, setting forth in detail, what I now consider the preferable embodiment of the invention, such disclosed arrangements of parts and devices constituting however, but one of various applications of the principle of the invention, certain modifications thereof being also shown.

In the accompanying drawings, in which the invention is fully illustrated:-

Fig. 1 is a plan view showing a preferred form of the invention associated with a printing machine, various parts being broken away to better illustrate the parts'below. For example, the rack bar 24 is broken away at one place to show the pawl 38 which lies beneath-and at another place to show the end of the ratchet bar 33.

Fig.2 is a side elevation of the mechanism shown in Fig. 1, as seen from the left side of the machine. I

Fig. 3 is a fragmentary view showing the positions of certain operative parts of the machine when viewed from the right side of the machine, certain parts thereof being shown in section and with the control finger in normal operating position Fig. 4 is a. partial side elevation of the right side of the machine.

Fig. 5 is a fragmentary sectional view substantially similar to Fig. 3, but showing the control finger in raised position.

Fig. 6 is a side elevation of the right side of the machine, showing a modification.

Fig. '7 is a fragmentary, sectional elevation of the modification shown in Fig. 6.

Fig. 8 is a side elevation showing a further modification.

Fig. 9 is a fragmentary sectional view of the modification shown in Fig. 8'.

Describing the invention with reference to the drawings, the blank advancing mechanism, designated generally by A, is shown in the drawings as an attachment to a primary machine, designated generally, by B, which we will assume is a printing machine of the well known Multigraph type.

The blank advancing machine A is of a known type, and, as regards its usual features, and excepting as to features and details of construction and operation, hereinafter particularly described and pointed out, may be of any usual or approved construction or operation and will readily be understood and can readily be supplied by mechanics familiar with such devices from an examination of the drawings, without a description thereof in detail. It should be understood that the blank advancing means of machine A is merely typical of suitable blank advancing mechanisms, and that other blank advancing means could be substituted therefor, without departing from the broad principle of the invention.

As shown, the machine A is driven by suitable operating connection with the driven shaft II] of the primary machine B, which extends transversely of the machine and is rotated in timed relation with the feed devices of the machine B.

Power for driving the machine A is applied from said shaft III by means of a disk I I mounted on said shaft for rotation therewith, and a connecting rod I2, opposite ends of which are pivoted to a crank pin I3 secured in said disk, and to the lower end of a member I4 which is fixed to a rock shaft I'I suitably journaled in the frame of a machine A. On the other side of the machine, a composite lever, generally designated I5, is mounted on the shaft II, the lower portion I4 being rigidly fixed to the shaft I1 and the upper part I6 of the lever being loosely journaled onthe shaft II, as best shown in Fig. 2.

The members I4 and IS in the particular embodiment of the invention shown, are normally in alinement and are yieldingly held in such relation by coiled springs 20 which connect an arm 2| which projects laterally from the member I4 and a corresponding projection 22 rigid with the member I6.

To retain the members I4 and I6 in alignment against the flexing action of the spring or springs 20 cooperating stops I8 and I 9. are provided on the members I6 and I4 respectively.

The arrangement is such that the member I4 is free to swing on its pivot against the tension of the spring or springs 20, when, in the operation of the mechanism, the member I6 is held against corresponding movement. This flexible connection is provided between the members I4 and I6 because the oscillatory movement of the member I4 is always the same, while that of the member I6 changes from time to time to suit the necessity of the occasion.

In operation, blanks in the pack receptacle of themachine A are adapted to be partly advanced therefrom by a usual friction roll 23, which is intermittently actuated to advance blanks in the direction of the feed devices of the machine B, by a usual rack-bar 24 pivoted to the upper end of the rock-lever I5, the teeth of which are maintained in operative engagement with a gear 25 loosely mounted on the shaft 26 to which the roll 23 is secured, by means of a channel-shaped guide member 21, pivoted to said shaft 26, to which said rack-bar 24 is slidably fitted so as to reciprocate therein. A pawl and ratchet mechanism, generally designated 28, has its ratchet wheel I6 fixed to the gear 25 and the pawls 11 (which are mounted in a cage 18) rigidly secured to the shaft 26 so that when the gear 25 is rotated in a clockwise direction, the pawls I! with their cage I8 rotate the shaft 26 and the ejector roll 23 in the same direction to advance the blanks.

With the described construction, it is obvious that, should the member I6 of the rock-lever I5 be locked against turning movement, the yielding connection between the members I4 and I6 of said rock-lever will permit the member I4 of said rock-lever to be freely swung further by the disk II.

In what I now consider the preferable embodiment of the invention, the means for and the manner of delivering blanks from the machine A to the feed devices of the machine B is as follows:

When the operative parts of the machine A are actuated to advance a blank from the pack receptacle, said blank would be advanced beyond the desired position in relation to the pick up mechanism of the machine B, unless means were provided to prevent such advancement. The machine of the present application embodies such means which will now be described, particular reference being made to Figs. 2 to 5 of the drawings, both inclusive.

Pivotally mounted in association with the friction roll 23 is a pivoted control finger 29, which is of such length that, normally, it will depend through a slot 30 formed in a plate 3| supported on the frame of the machine A, said finger being arranged in the path of movement of blanks advanced from the pack receptacle of said machine. The free end of the control finger 29 is spaced rearwardly from a stop 29 of the primary machine B, which stop defines the pick-up position of blanks delivered to the feed dvices of said primary machine. The blanks are supported and guided in their movement from the machine A to the feed devices of the machine B by the plate 3|, which, for reasons presently described, comprises a part or section which may be slightly convexly curved, as shown at 32. Said means also comprises a ratchet-bar 33 mounted so as to be movable endwise in a fixed guide 34 secured to the frame of the machine A. Said ratchet-bar 33 is maintained yieldingly at. the limit of its retraction by a spring 35, see Fig. 2, opposite ends of which are secured topins 3E, 36', secured in said ratchet-bar and in a bracket 31 secured to the arm l6 of the rock-lever I5, respectively.

Also, when free to respond thereto, reciprocating movement is imparted to the ratchet-bar 33 in operation, it being retracted by the spring 35 on each actuation of the rock-lever I5 to partly advance a blank from the pack receptacle, and being advanced on the retraction stroke of said rock-lever, by contact of said rock-lever with the pin 36 secured in said ratchet-bar.

Also, in accordance with the present invention, my improved machine comprises means, controlled by turning movement of the finger 29, for locking the ratchet-bar against endwise movement under the pull or tension of the spring 35.

As shown, the means for this purpose, comprises a pawl 38 pivoted to a lug or projection 39 on the ratchet-bar guide 34 in position to engage the teeth of said ratchet-bar, the ratchetbar guide being cut away, as shown at 40, to permit such engagement.

In the preferable construction shown, the pawl 38, unless prevented, will fall by gravity aided by a spring if necessary as shown at 59 in Fig, 6 into engagement with the teeth of the ratchetbar 33 and is adapted to be turned pivotally to disengage said pawl from the teeth of the ratchetbar, by a finger 4| on thearm 16 of the rocklever i5, which is adapted to contact with the under side of a laterally extending stud Iii rigidly attached to said pawl, as said rock-lever approaches the end of its retraction stroke, as will readily be understood, thus disenga ing the pawl from said ratchet-bar 33.'

In accordance with the invention, the pawl 33 is maintained normally out of engagement with the teeth of the ratchet-bar 33, and is intermittently engaged therewith, by means rendered operative by lifting movement of the control finger 29, as by the passage of a fed blank between said finger and the plate 39.

Said control finger is secured to a rod 32 and is in position, normally, to depend through the slot 313. Specifically, said finger is formed at the inner end of said rod, which is rotatably fitted to the bore of a sleeve 33, the outer end of which is rigidly secured in a side frame member of the machine. The outer end of said'rod 42 extends outwards beyond the end of said sleeve and secured thereto so as to turn therewith, is a crank arm 34, secured in which is a pin 45 which projects laterally into the path of movement of a fixed projection 43 on the pawl 33, and applied to the crank arm at is a light coil spring M adapted to turn said arm pivotally Excepting when the pawl 38 is turned pivotally to disengage it from the teeth of the ratchet-bar 33, the pin it will rest against the nose of the projection 63 and will thus be held from engaging said notch.

Also, when the pin as is in engagement with the notch 68 in the projection 33 on the pawl 33, in which relation said pawl will be disengaged from the teeth of the ratchet-bar 33, disengagement of said pin it from said notch 33-thus permitting the pawl 38 to fall into engagement with the teeth of said ratchet-bar 33, thereby locking said bar against endwise movement by the spring 35-may be effected by lifting movement of the control finger 29, as by advancement of a fed blank between said finger and the plate 39.

As heretofore explained, the progress of a blank from the pack receptacle and through the machine A, by actuation of the friction roll 23, is performed in two separate stages, the first stage being completed when the forward edge of the blank lifts the finger 29 and causes the engagement of the ratchet-pawl 38 with the teeth of ratchet-bar 33, and the second stage being completed when the arm it of the rock-lever I5 of the machine contacts with a stop 49 on its feeding or ejecting stroke, thus advancing the leading edge of 9. fed blank into position for engagement by the feed devices of the primary machine-during both of which stages, blanks are held and their positions in the machine defined by the advancing roll 23, fed blanks finally being withdrawn from engagement with said roll 23 by actuation of the feed devices of the primary machine 13.

The stop 49 as shown, comprises a screw adjustably mounted on the ratchet-bar 33 and with which the backward edge of the arm I6 01 the lever I5 is adapted to contact.

Its function is to limit the backward swinging of the arm l6 after the rack-bar 33 has been locked against movement by the pawl 38.

As has been explained the projection 36 on the ratchet bar 33, to which one end of the spring 35 is attached, is engaged by the forward edge of the arm i6 of the lever IS on its forward movement and the spring 35 maintains the stop'tii in contact with the arm it on the backward or blank advancing swing of the lever 05 until the pawl 38 is dropped, to engage the rack-bar, while the lever i5 moves on in its blank advancing movement until it contacts with the stop 49. At this time the ratchet-bar 33 by which the stop at is carried is locked by the pawl 38 against further backward advancing movement and consequently the arm i3 is stopped thereby. It will now be seen that by the construction described the blank advancing swing of the arm it is limited by the stop 39, which is carried by the ratchet bar,

and that the possible backward movement of the arm it after the pawl is engaged with the rack 33 is that permitted by the spacing of said stops. Such permitted movement of the arm 03 I is practically commensurate with the second stage of the advancement of the blank through the machine and the stop a9 is made adjustable so that the blank can be stopped accurately at the pick-up position of the primary machine B.

It is intended that after the completion of the first stage of advancement of a blank the second stage shall uniformly advance the blanks 2. defmite-predetermined distance so that the successive blanks shall be similarly engaged by the pick-up mechanism of the primary machine B for the'purpose of the accurate registration desired.

I have found, however, that due to a number of causes, slight slippage of the devices of said primary machine on fed blanks sometimes occurs, which results in slightly imperfect registration of the impressions made on different blanks of a series, which is, of course, undesirable.

In accordance with the present invention, I have overcome this objectionable feature by the provision of auxiliary means for imparting slight intermittent rotation to the advancing roll 23, timed to operate after completion of the blank advancing stroke of the main device of the machine A and simultaneously, as near as may be, with actuation of the feed devices of the primary machine B, whereby said feed devices will be relieved from all duty other than that required for handling a single unrestrained blank, with the result that practically perfect registration of impressions imprinted on successive blanks is obtained.

As shown, said auxiliary means for actuating said roll 23 comprises a rod 5i) which extends transversely of the machine A and is mounted to oscillate in bearings formed in the side frames thereof, formed on'which is a crank-arm 5!, se-

cured to the end of which is a rack-bar 52, which is applied for imparting intermittent rotation to the roll 23, in substantially the same manner as the primary actuating mechanism consisting of the arm I6 of the rock-lever I5 and the rackbar 24.

As shown, oscillation is imparted to the crankarm Si by means of a lever-arm 53 secured to the end of said rod, mounted on a stud secured in the end of which, is a roller 54, which, in operation, is maintained in contactwith the outer edge I I of the disk II by a spring 55, which connects the crank-arm 5| with the frame of the machine A, said outer edge II' of the cam disk II being suitably cam shaped for this purpose.

The upper part I6 of the lever I5 is oscillated by its coaction with the lower part I4 of the composite lever, this latter part being continuously oscillated by its connection through the shaft II, arm I4 and link I2 t the cam disk II. The forward movement of the arm I6 operates through the finger 4I striking the underside of the stud 15 to release the pawl 33 from the ratchet bar 33. On the rearward stroke of the arm I6, the ratchet bar moves to the right in Fig. 2 until the rack bar 24 has advanced the sheet sufficiently to operate the control lever 29 whereupon further movement of the ratchet bar 33 to the right is prevented by the drop of the pawl 38. This fixes the position of the stop 49 and the continued movement to the right of the arm I6 which determines the further advancement of the blank is limited to the precise distance defined by the distance between the point at which'the ratchet bar 33 stops and the position of the stop 49. As a result, the leading edge of the blank will always occupy the same position after each operation of the feeding device.

In actual operation due to the occurrence of slight slippage of the friction roll 23 on the blank being advanced or due to the next blank below the one being advanced being dragged slightly forward by the blank being advanced, the presentation of the forward edges, of the successive blanks being advanced to the control finger 29, does not always occur at the same point in the blank advancing movement of the lever I5.

Furthermore due to the fact that the stop 49 on the rack bar 33 moves in a horizontal line and the lever I swings in an arc, the allowable movement of the arm I6 of the lever I5 after the rackbar 33 has been locked, due to the lifting of the control finger 29, would not always be the same, as the space between the stop 49 and the adjacent edge of the arm I6 of the lever I5 would vary due to the varying inclination of the arm I6 at such time. To compensate for this variation the adjacent edge of the arm I6 of the lever I5 is provided with a notch 56 Which is deeper toward the free end of the arm I6 so that as the arm I6 is swung to the right (Fig. 2), on the blank advancing stroke, the allowable movement of the arm I6 after the rack is locked will be maintained substantially constant. It should be understood that the notch 56, as shown, is an approximation, but shapes the edge of the arm which cooperates with the stop 49 to effect the second stage of advancement of the blank with sufficient accuracy for all practical purposes.

As a modification of the invention I contem-= plate a construction in which the blanks advanced by the machine A are advanced from the pack directly to the desired position relative to the pick up mechanism of the primary machine B, in a single stage of advancement instead of a plurality of stages, as shown in connection with the preferred embodiment of the invention in Figs. 1 to 5, and heretofore described.

In Figs. 6 to 9 inclusive, I have shown two different modifications of my invention, which will now be described.

All of said machines are of the same general type as the preferred form shown in Figs. 1 to 5, inclusive, of the drawings, as regards their usual features and excepting as regards features of construction and operation hereinafter particularly described and pointed out, and may be of any usual or desired construction, and will be understood and can readily be supplied by mechanics from an examination of the drawings, without a description in detail thereof.

The same and corresponding parts are designated by the same reference characters in all figures.

Referring now to Figs. 6 to 8, A designates the blank separating and advancing machine as a whole, and B designates the associated primary machine as a whole-and which we will assume is a known form of commercial printing press of the Multigraph type.

The principle involved in the modification shown in Figs. 6 and 7, is that of the continuous or uninterrupted advance of the blank from the pack to the pick-up position of the primary ma chine B, and the stopping of the application of power to the blank advancing element simultaneously with the advancement .of the forward edge of the blank to said pick-up position. For effecting such operation, I make use of the control finger 29 described in relation to the preferred form of the machine except that its end, with which the forward edge of the advancing blank engages, is positioned, in close relation to the stop of the primary machine instead of spaced therefrom as in the preferred form.

In the machines shown in Figs. 6 and 8 the advancement of blanks from a pack is effected by means of the friction roll 23, to which intermittent rotation is imparted by suitable operating connection with a source of power, consisting, as shown, of a crank-disk II secured to the drive shaft ID of the primary machine B, and a connecting rod I2, one end of which is pivotally connected to a crank pin I3 secured in said crank disk, and its opposite end to the lower end of the lever I5, pivoted to a stud I'I secured in the machine frame, and which comprises separate arms I4 and I6 individually pivotally mounted on the pivot I1 and normally maintained at the limit of their fiexure in one direction, defined by the stops I8 and I9, by the springs 20, applied to the pins Al and 22 secured in said lever members, respectively.

The feed devices of the machine comprise the friction feed roll 23, to which intermittent rotation to advance blanks from a pack is imparted by driving connection with the oscillating lever I5, substantially as hereinbefore explained in connection with the preferred embodiment of the invention, and devices which control the movement to permit oscillation of said lever lv in a direction to withdraw blanks from the pack and advance them to the feed devices of the primary machine by means of a pawl 38 pivoted to a lug or projection 39 secured to the ratchetbar guide 34, said guide being cut away, as shown at 40, to permit engagement of said pawl with the teeth of said ratchet-bar the pawl being normally held in engagement with the teeth of the ratchet-bar 33 by a'spring 59 secured as shown on the ratchet-bar guide 34.

The blank control devices of the machine also comprise a control finger 29 connected to the inner end of a rod 42 rotatably mounted in a sleeve 43 the outer end of which is secured in a side frame of the machine. The end of said rod projects out through said sleeve, and secured thereto so as to turn therewith, is an arm 69 against which a rod Bl, secured in the pivoted end of the pawl 38, rests, the relation being such that normally said operating lever l5 and ratchet-bar will be locked against movement to eject blanks. Said means also comprises means for turning said pawl '38 pivotally to disengage it from the teeth of the ratchet-bar as the lever l5 approaches the limit of its retraction movement. As shown, said means consists of an arm 62 formed on and which depends from said pawl adjacent its free end and in such relation that the rock-lever I5 will first contact with the outer end of said depending arm, with capacity for further movement sufllcient to turn said pawl to raise it out of engagement with the teeth of said ratchet-bar against the holding action of the spring 59.

Such turning movement of said pawl will swing the outer end of the rod 6| downwards to bring the outer end thereof below the end of the arm 60, and the relation being such that slight turningmovement will be imparted to said arm 60 causing it to swing over the'free endof said rod 6! and prevent the pawl 38 from dropping down to engage the rack 33. The relation is such that when the arm fill has locked the pawl 38 against engagement with the rack-bar 33 the control finger 29 has dropped into the position indicated.

in dotted lines in Fig. 7 and is then in position to be raised to the full line'position by the forward edge of an advancing blank. Simultaneously with the raising of the finger 29 high enough, which occurs just as the forward edge of the advancing blank reaches the stop 29"of the machine B, the pawl 38 is released and is depressed by the spring 59 into engagement with and locks the ratchet-bar 33 against further application of power to the friction wheel 23, through the lever l5 as heretofore described, by the pin and slot connection of the lever arm l6 and ratchet-bar 33.

At such time the blank advancing mechanism including the roll 23 may have slight momentum which will tend to advance the blank slightly further, but this will not be effective to destroy the registry obtained as the blank can buckle down, as shown in dotted lines at 63 to take up or allow such slight overthrow.

The principle involved in the modified form of the invention shown in Figs. 8 and 9 consists in lifting the control finger 29 by the buckling of the blank after it has been advanced into contact with stop 29 of the primary machine B.

The blank advancing and control mechanism in this second modification is substantially the same as that shown in Figs. Sand 7 except as to the changes and differences hereinafter noted,

As best shown in Fig. 9, the free end 64 of the control finger 29 is spaced rearwardly from the stop 29' of the primary machine, and when not engaged by an advancing blank drops down into the path of the advancing blank as shown in dotted lines Fig. 9.

There is a concave guide member 65 provided,

secured to the guide plate 3|, the function of which is to cause the advancing blank to buckle upwards, and prevent it from buckling downwards as shown in Fig. 9, when it is pushed against the stop 29', andlift the finger 29 to its full line position and thus lock the arm 16 of the,

lever l5 against further blank advancing movement, as explained in relation to Fig. 6, thus stopping the application of power to the friction roll 23 in a similar manner.

To prevent the possible excessive rise of the forward edge of the blank above its proper path by the curved guide 65, I provide a downwardly projecting guide plate 66 fixed above the normal path of the blank which, if the forward edgeof the blank comes into contact therewith will guide.

the forward edge of the blank downwardly and into. contact with the stop 29'.

As many other modifications will readily suggest themselves to one skilled in the art, I do not limit or confine the invention to the specific details of construction and operation herein shown and described except within the scope of the appended claims.

I claim:

1. In a blank separating and advancing machine, means for separating and advancing a blank from a pack, controlling means disposed in the path of the advancing blank at a predetermined distance from a predetermined final position of the blank, and means controlled by said controlling means for limiting advancement of the blank after it has been advanced to said controlling means, the amount of such limited advancement being equal to the distance between the said controlling means and the contemplated final position of the blank.

2. The blank separating and feeding machine defined in claim 1, the controlling means of which comprises a pivoted finger disposed in the path of the separated and advancing blank, and means controlled by said finger for limiting, to a predetermined amount, advancement of the blank after the blank has been advanced to said finger. 3. In a blank separating and advancing machine, a separator member, means for actuating said member'to separate a blank from a pack of blanks and advance said blank to a blank advancement control member disposed in the path of said blank, said control member being operable by the advancing blank to limit the advancement of the blank beyond said control member.

4., In a blank separating and advancing machine of the type described, a separator roll, a

rack for operative engagement with the said.

separator roll for intermittently rotating said roll to separate a blank from a pack and advancing it through the machine, a swinging arm for actuating the rack to rotate said roll,.means for limiting the movement of the rack comprising a definite.

5. The invention specified in claim 4, in which the means for controlling advancement of the blank comprises a swinging finger dependent into the path of the blank and a ratchet pawl controlled by said finger, the arrangement being such that swinging movement imparted to said finger by an advancing blank will effect engagement of the ratchet pawl with the teeth of the ratchet bar and thereby limit pivotal movement of the arm, to which the rack bar is connected, in

' a direction to separate and advance blanks.

6. The blank separating and advancing machine specified in claim 4, in which the stop which limits turning movement of the pivoted arm for actuating the rack bar for rotating the blank separator roll is adjustable.

7. The blank separating and advancing machine specified in claim 4, which comprises a plate .for supporting and guiding advancing blanks, said plate being provided with a slot through which the swinging arm depends.

8. The invention as defined in claim 4, the ratchetbar having a'straight line forward and back movement and the swinging arm an oscillatory movement, and the rear edge of the swinging arm formed to compensate for the various angular positions of the arm when it contacts the limiting stop on the ratchet-bar, for

maintaining the second stage of movement of a blank through the machine at a constant amount after the ratchet-bar has been locked against further rearward movement.

9. In a machine of the kind described adapted to advance a blank to the pick-up position of an associated machine, a swinging arm for operating the blank advancing mechanism, a movable stop for cooperation with the arm for limiting the blank advancing movement thereof, means operable by an advancing blank to lock the stop against further advancing movement, and the cooperating edge of the arm formed to compensate for various positions of the arm at the instant of the locking of the stop so that the remaining advancing movement of the arm shall remain substantially constant.

10. The invention as defined in claim 4, the stop on the ratchet-bar, which limits the blank advancing movement of the swinging arm, be-

. ing adjustable. a

11. In a mechanism of the kind described, a friction roll for separating a blank from a pack and advancing the blank to the pick-up position of an associated primary machine, means for applying power to said roll for rotating same, means forstopping the application of power to said friction roll when the blank reaches said pickup position, the arrangement being such that the blank may still be engaged by said friction roll when the feed devices of the primary machine engage the blank to withdraw same, and auxiliary means for applying rotative power to said friction roll substantially simultaneously with engagement of the blank by the feed devi ces of the primary machine to assist the primary machine in withdrawing the blank and prevancement of said arm is predetermined and venting slippage as the primary machine begins to advance the blank.

12. In a mechanism for separating a blank from a pack and advancing the blank to the pickup position of an associated machine, a friction device for moving the blank, the associated ma chine having a stop arranged in the path of the blank and defining the pick-up position thereof, means for intermittently applying operating power to said friction device, a movable finger in the path of the blank for controlling the application of operating power to said friction device, the arrangement being such that the forward edge of the blank will move said finger to a position to stop the application of power to said friction device substantially simultaneously with the contact of said forward edge with said stop of the associated machine.

13. In a mechanism for separating a blank from a pack and advancing the blank to the pick-up position of an associated machine, a friction device for moving the blank, the associated machine having a stop arranged in the path of the blank and defining the pick-up position thereof, means for intermittently applying operating power to said friction device, a movable finger in the path of the blank for controlling the application of operating power to said friction device, the arrangement being such that the advancing blank is buckled into operative contact with said finger after it contacts with said stop of the associated machine and thereby the application of operative power to the friction device is stopped.

14. The invention described in claim 9, and an operative arm, yielding means connecting the operative arm to the swinging arm, the arrangement being such that at times when the swinging arm is held against blank advancing movement the operative arm is free to be swung back and forth.

15. In a blank feeding machine, means for separately advancing blanks froma pack in the direction of an ultimate position, means rendered operable by an advancing blank when the blank has reached a predetermined intermediate position for arresting the feeding action of the blank advancing means when the blank has reached said ultimate position.

16. In a blank feeding machine, power operated means for separately advancing blanks from a pack in the direction of a contemplated. ultimate position, means rendered operable by an advancing blank when it has reached a predetermined intermediate position for stopping the application of power to said blank advancing means when the blank reaches said ultimate position.

17. In-a blank feeding machine, means for separately advancing blanks from a pack in the direction of contemplated ultimate position, a blank advancing roll, means for intermittently rotating said roll for advancing blanks from the pack, and means controlling the blank advancing action of said roll to limit the advance of the blank to a predetermined amount beyond a predetermined intermediate position.

WM. WARD DAVIDSON. 

